Flying in and out of Denver, and going south towards Colorado springs, out to the sand dunes, and Mesa Verde, and then back up and round to RMNP.
Im spending ~8 days out there.
Anything Im missing or need to see?
Anyone up for a hike?

Peak wildflower season is exactly in one month, so your timing is good in that regard.

Drive up Mt. Evans out of Idaho Springs, which would be a must and is superb for sunrise and sunset. Itís also the best spot for mountain goats, which is a sure bet shortly after sunrise.

On your way north out of Mesa Verde (from Durango), I would allocate at least 2-3 days in that region. If you make it to the Telluride side, which is a worthy destination, definitely take the free gondola ride and get off at the top for the impressive views. Heading north out of the San Jaun Mountains, I would suggest a detour at the expense of filling up more space on a memory card by taking Owl Creek Pass out of Ridgway to Highway 50, my favorite back road in the state. From there, head west to Black Canyon, which will be a must-see out of Montrose.

From Montrose, I would suggest going north to Delta and take 92 and 133 east. From here, you have two options:

Option 1: If you want more mountains, drive Kebler Pass to Crested Butte. While in Crested Butte, a drive up Paradise Divide, via Slate River Road, would be worth your time. From Crested Butte, head south to Almont, then over Cottonwood Pass (sweet sunset area), then north to Leadville and onto RMNP or your next destination. If inclined, you could take 82 back to the west to Aspen and stop in at the Maroon Bells, which is ~55 miles one-way over Independence Pass, or:

Option 2: Continue on 133 through Carbondale and Aspen (Hwy 82) and over Independence Pass to Leadville.

This all assumes you have a car. If you happen to have a 4WD vehicle, then you've opened a whole new world with some additional options.

So, your first stop is Colorado Springs, probably the Garden of the Gods (GOG), rated last week as the best city park in America (hard to think of it as a city park). You are probably coming down I25 from Denver and you might want a quick exit off on Northgate Road to see the Air Force Academy Chapel (2nd exit down from Monument Exit). Back on I25 you take Garden of the Gods Blvd Exit (duh), west to 3oth street and left (south). Why this detail, it is well marked, well on 30th there are places soon after you turn. On the left is Mesa Road which goes up over the GOG Visitors Center and affords a great view of the park. When there is fresh snow blanketing the area it is like wonderland, not too shabby in July either in the morning light. As you might know, morning has the best light for the GOG.

Also right off 30th is a religious retreat that I believe is signed as "The Navigators". Burns me up, it is what we locals call Glen Eyrie Castle and it should be in the public domain, not some retreat. It was the home and lands of General Palmer who founded Colorado Springs (COS). Beautiful land, plenty of wildlife, and good trails which used to be open for hiking. Unfortunately, the trails are still closed because of the Waldo Canyon Fire and may never re-open. Queen's Canyon was one of the best hikes in this part of Colorado. Only way to get on the grounds is if you rent a room and can stay there: http://www.gleneyrie.org/Visit-the-Castle/Stay-Overnight. I always thought this would be cool and fairly reasonable, and sure beats any other hotel in the Springs. Convenient too, I mean, you could roll out of bed in the morning in your PJs and walk or drive over to the GOG, then come back for breakfast. I have seen more wildlife on their grounds than the rest of Colorado. So, what about the Garden?

In the Garden there are many trails and a few photographer trails too that are closed to the public (but we know where they are). My favorite is Rattlesnake Ridge, just watch out for the park rangers and snakes. (There are a few more that are more hazardous which I shouldn't say here). After the main parking area, a little up the one way loop road is a really good vantage point, one of the few that is a good evening spot too. There is a balanced rock further along the road that every one photographs, but just before it, on a dirt road on the right, marked Rampart Range, there is another balanced rock that few people visit. The Siamise Twins trail is a nice short hike, sometimes called Window Rock, because you can frame Pikes Peak in the hole through the rocks. Do stop in the Visitors Center, they have some good maps of the park. On the wall they may have for sale a picture of Kissing Camels framed by two old oaks. That is another photographers trail that common folk are not allowed up (photographers neither, but you know...)

You sound like you plan to drive south on I25 to Walsenburg, then catch Hwy 160 to the Sand Dunes. Go south a bit more to Trinidad and pick up Hwy 12, the Highway of Legends (google it) and come back to Hwy160 around La Veta - great scenic drive. At the Dunes the Great Sand Dunes Lodge is fairly reasonable and every room has a view of the dunes. Nearby is Zapata Falls and on the way along 160 is Fort Garland. There used to be, maybe still is, a ranch (Zapata Ranch?) where they would drive you out among a buffalo herd to photograph. OR, leaving GOG, you could go west on Hwy 24 instead and see many old mining towns like Victor (nice cemetery and mining trails), Cripple Creek (just went there for Donkey Derby Days) and St Elmo. So much to see and so little time... and I have not even got to the mountains. So this is a start for your trip and Darren covered the mountains well so all I will just say is"Pssst, Crested Butte" (and if go there, look for the book "Enjoying Crested Butte the Easy Way). Best advice on trails and roads for fall color and wild flowers if you spend any time there. You will be there just after the Crested Butte Wildflower Festival, they never get it right and you just may...You are welcome to PM me.

You cannot spend too much time in the San Juans...Silverton, Ouray, Ridgway, Telluride. Then, Lake City, Gunnison and Crested Butte, followed by Aspen and Leadville. If you like mountains, you'll want to move there. Ride the Durango-Silverton train (make reservations in advance).